﻿<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8" />
<title>闭包演示</title>
<style type="text/css">
    p {background:gold;}
</style>
<script type="text/javascript">
    var arr = [];
    arr.valueOf() === arr; // true
    document.write({} + []);
</script> 
</head> 
<body onload="init();"> 
    <script>
        var Option1 = 2
        var Option2 = 4
        var Option3 = 8
        var Option4 = 16
        var Option10 = 1024
 
        var SelectedOptions = Option3 | Option4 | Option10; //= 1000100100
 
        if(Option2 & SelectedOptions) {
            alert(SelectedOptions);
        }
    </script>
<p>产品 0</p> 
<p>产品 1</p> 
<p>产品 2</p> 
<p>产品 3</p> 
<p>产品 4</p> 
</body> 
</html> 